BP, like other refiners, is seeing a rise in hydrogen consumption per barrel of crude oil due to tighter product specifications and the increased processing of heavier crudes. To meet both the present and future requirements, the 255000 BPSD BP Carson refinery initiated a hydrogen pinch study to optimise the refinery’s hydrogen system.

In the project completed in December 2000, Linnhoff March aimed to:

	Avoid investment in infrastructure
	Reduce hydrogen system operating costs
	Improve hydrogen quality supplied to key processing units
	Improve energy efficiency and environmental impact

A total of 14 projects were identified and represented in a RoadMap. All project combinations avoid the need for infrastructure investment, with the most attractive option in terms of hydrogen system operating cost saving a total of $4.5 million per year.

A significantly more attractive solution was proposed that uses existing pipework and compressor capacity to save $3.9million per year in hydrogen supply costs. However, the significance of this solution lies in the increase in supply purity achieved to five processing units, including a 1% purity increase to one of the principal units on site.

A global balance showed that the projects reduce energy consumption by 6.7MW, with a corresponding saving of 25000t per year in CO2 emissions.